25 July 2008

Jug Orchid - Pterostylis recurva

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Jug Orchid - Pterostylis recurva

A very striking orchid and not easily overlooked by having a large flower of around 35 mm (11/2"), which is exposed above low vegetation on granite outcrops. Never in large colonies, but usually scattered plants can be found on most large rocky outcrops. Apparently it also grows in other habitats elsewhere, but I have not seen that in this region.

The unusual jug-like flower is an indication that this species is not closely related to any other Pterostylis species, so you will like-wise not be confused regarding identification, it being quite unique. Flowering time is usually from August to October, so don't miss it as it is worth seeing.

My Other Blogs

There are three blogs that I manage, so if you find one with no recent posts, please try one of the others. They all deal exclusively with the flora and fauna of the Esperance region of Western Australia, so may also be of interest.

Esperance Environment

Esperance is situated on the coast a little over 600 km ESE of Perth and 350 km south of Kalgoorlie. Temperatures are generally mild with a dominant winter rainfall of around 600 mm a year, although this drops rapidly away from the coast.

The near coastal areas comprise alkaline sands formed into stable vegetated dunes often over limestone. Here the vegetation is less diverse than further inland and has many fast growing colonising species, some of which can become weedy and invasive elsewhere.

Just behind the coastal dunes are deep acid sands with many ephemeral swamps. It is this coastal heath zone, where the greatest plant diversity is to be found. However both regions contain their own species that are not to be found in neighbouring habitats.

Behind the coastal heath is the mallee (much converted to broad-acre wheat farming), here the soils are generally heavier, but mainly still well drained with a fine sand/clay content. These soils are usually acid to neutral, but generally overlie limestone, or to a lesser extent clay.

Another important soil type is a gravel that is mixed with a fine sand/clay base that is often used for making rural roads; these gravels are usually covered to varying depths with a sandy soil and support considerable flora diversity.

Saltlakes are common throughout the region, varying greatly in size. Some in the drier regions often have a very high gypsum content, resulting in dry, light grey, talc-like mounds, which support a more limited number of species, but which are commonly unique. Different species grow on islands within the lake or around the edges in soils, which tend to contain more sand or clay and less gypsum.

To complete the main habitats of this region are the numerous granite outcrops, these span from the coast to the mallee, and many contain flora found nowhere else. This is especially true in the drier regions as the granite collects and directs rainfall into well-watered zones to permit the survival of plants with a higher water/temperature requirement.

Wildlife is largely dependent on rainfall and vegetation type, so Esperance being favoured with extensive habitat diversity is likewise rich in species. Threats to this environment are currently inappropriate land management, introduced weeds and predators like cats and foxes. All of which impact heavily on the flora and fauna.

About Me

I have always been passionate about nature and for many years have lived in the bush and so been privileged to witness the private lives of indigenous wildlife and the floristic wonders of Western Australia's often unique flora.

These blogs are a serious photographic record of the biota of the Esperance region and will contain species I have personally photographed, conscequently it will be updated as new species are filmed or better photographs taken.

Should any errors be noticed, please point them out so they may be corrected. Hopefully, these blogs will be used to identify the flora and fauna of the SE coastal and hinterland region of Western Australia, or like me, just to wonder at the magic of its diversity.

Should you wish to contact me direct, please email: w.archer.esperance@gmail.com